PETROL!!

[Ian]

Hi all,
I would like a bit of feed back on this one if you can.

Our Chem teacher of many years has gone and been replaced with a new one. The new girl has chem training but has not taught chem before. Fortunately for her, the previous teacher has left a term of chem work for the year 10 class. Today, they did a "Heat of Combustion" prac with Spirit Burners. One of the fuels they were supposed to ignite in the spirit burners was PETROL.

I felt very nervous! She felt very nervous! We replaced the petrol with Butanol.

Now given that Petrol is a "Red Dot" chemical, can any body tell me if it is safe to light a spirit burner full of petrol (irrespective of it being year 10 boys (and girls) being trusted to do it.) What is the difference between that and a "Molotov Cocktail"?

Was my nervousness warranted?

regards
Ian

[Slartibartfast]

The lids of our spirit burners are on a fairly coarse thread that don't seal enough for my liking especially for petrol! ANY vapours escaping around the base of the lid and up it goes.

Also the burner would have to be almost completely full to minimise vapours trapped within.

You can in a controlled environment try and light liquid petrolium itself and it won't work, but get the air/fuel ratio even remotely right.........

[smiley]

Right on Ian, nervousness warranted in my opinion. The potential for the rapid evolution from burner to Molotov was huge.

Cheers, K

[rp]

Hi
We had a teacher use diesel last year and she did it outside but it caught on fire and exploded.not a good idea.